As one elephant needs as much as 200 kilograms of food and 200 litres of water a day, villagers in Prachuap Khiri Khan's Sam Roi Yod district were understandably alarmed when they were invaded by herds of up to 50 elephants.

"One elephant invasion means that the villagers' investment for the whole year is gone," said Prayat Kaewkan, who headed a research project - aimed at reducing the impact of such invasions -  sponsored by the Thailand Research Fund. Farmers bordering the national park and sanctuaries of the eastern and western regions know this issue well. They have long suffered elephants invading their farmland - and the problem seems to get worse every day.

Dr Mattana Srikrajang, of the National Park, Wildlife and Plant Conservation Department, said the wild elephant population had increased by about 10 per cent a year while forestland was becoming limited, leading to a shortage of food and water for the animals.

Villagers tried various methods to drive away the elephants, including firing guns, letting off firecrackers and erecting low-voltage wire fences, but they were effective only for a short while, as the elephants were smart and learned to adapt quickly. From storming in herds at first, the elephants learned to sneak into villages in smaller groups, to having no fear of loud firecrackers, and to use fallen trees in breaking through wire fences.

Villagers tried providing the elephants with food and water at designated locations, which only brought more spoiled beasts even closer to their community. Some people resorted to high-voltage electric shocks or fatally wounding jumbos.

"Violence only breeds violence," one villager said, citing a case of a neighbour who put up a high-voltage fence that killed an elephant, just to have 20 beasts come and destroy his home. In another case, an elephant was shot once but later charged a gun-carrying person in self-defence.

Thus emerged the Wana Kaset (Agriculture Park) project - growing diversified crops on farmland - as one solution suggested by the research team at Khao Ang Ru Nai Wildlife Sanctuary.

Researcher Thawat Kiaetseri explained that elephants eat single-type crops grown in vast plots of land such as potatoes, sugar cane and pineapples. The Wana Kaset solution was to use crops and plants that elephants do not like or that can withstand being stamped on.

Some 30 families joined the project. They grew edible plants such as acacia pinnata and melientha suavis pierre at areas bordering forestland, along with trees such as hopea, neem and mahogany. So far, the tactic has greatly reduced elephant invasions.

Chanthaburi farmer Wattana Khamrakkietcharoen said the Wana Kaset method also released farmers from growing crops that did not yield stable incomes. Four years after he adopted the Wana Kaset approach, he managed to pay off debts and while there were four or five elephant invasions a year in his neighbourhood, they did not come to his farmland.

Wattana's neighbour Kanya Kachita confirmed the success, saying elephants had not disturbed her farm since they changed from a fruit orchard to a Wana Kaset farm.